Variable-speed gearing.



No. 7o|,a7s. Patented lune In,A |902. F. w-. Gannon.

VARIABLE SPEED GEARING.

(Appiiceion med Feb. 2e, 1902.) 'ma Model.) 2 sheets-sheet l.

Y r. w. Gannon. VARIABLE SPEED GEARNGL.

(Appl'iionlmed Feb. 2e, 19172.)

2` Sheets-Sheet 2.

y (No Model.)

mi ohms PETERS co Puma-urna wnmmon. u. c.

UNITED STATES' PATENT EEICE,

FREDERICK W. GORDON, OE "IlIARTEOAR'D,l CONNECTICUT, AssIGNOR TO PRATT aWHITNEY COMPANY, OE HARTFORD, CONNECTICUT.

VARIABLE-'s PEI-:D G EARING.

SPECIFICATION forming part of Letters Patent 701,876, dated June 10,1902.

Application filed February 26, 1902. Serial No. 95,820. (No model.)`

To all whom t may. concer-n:

Be it known that LFREDERICK W. GORDON, a citizen of the UnitedStates,residing at Hartford, Hartford county, Connecticut, (post-of# iceaddress, care Pratt & Whitney Company,

Hartford,Connecticut,) have'invented certain new and useful Improvementsin Variable- Speed Gearing, of which the following is specification. .fThis invention pertains to a system of gear'- ing for transmittingmotion from a' drivingshaft rotating at uniform rate to one or morevdriven shafts at variable rate. The system is applicable to manysituations in machine construction, and I have thought best toillusstrate it in connection with the driving ofthe feed devices of anengine-lathe.

The invention will be readily understoo from the following description,taken in con`-l nection with the accompanying drawings, in

the mechanism as viewed from the\left handA of Fig. 1; Fig. 3, avertical transverse section taken in the plane of line a of Fig. 1 andviewed from the left of that plane; and Fig. 4, an'end elevation asviewed from the right in Fig. 1, parts appearing in vertical transversesection in the plane of line b of Fig. 1.`

In the drawings, 1 indicates the bed of an ordinary engine-lathe; 2, thehead-stock of the lathe; 3, the lathe-arbor; 4, the usual change-gearspindle taking its motion from the arbor; 5, the usual change-gearthereon; 6, a shaft supported by the bed parallel with the lathe-arbor;7, a change-gear on shaft 6; 8, intermediate gear mechanism in the trainof change-gears to cause gear 5 to transmit motion to gear 7; 9, a shaftsupported by the bed parallel with and near shaft 6; 10, a casinginclosing the general gearing and secured to the lathe-bed andfurnishing the protecting and supporting housing for certain gears thelength of the latter being substantially equal to the length oftheseries of gears 12, lwhich gears 12 will hereinafter be referred toasthe cone-gears, the preferable arrangement'being that these gears bearranged in step-like succession 13, a wall of casing 10, arrangedconcentric with shaft 6 and provided With an-oblique longitudinal slot;14,

Vabracketseated against the inner surface of concentric wall13 andadapted for longitudi-v nalfand circumferential adjustment upon saidwall'; 15, aclampengaging the bracket 14 and the slot in wall 13 andserving to clamp the bracket inadj usted position upon the wall; 16, anidle gear carried by bracket 14 and constantly engaging long pinion 11and adapted by the adjustment of the bracket to be put into engagementwith anyselected one of cone- 12, this gear 21 being in the plane ofgears 19 and 20but free of engagement with them; 22, a rockingtumblerwith -itspivot-axis ooinciding with shaft 9; 23, a gear" carried by thistumbler and constantly engaging gear21, and adapted by the 'adjustmentof thel tumbler to be thrown into engagement'with either gear 19 or 20,and' 24 a detent forlocking tumbler 22 in its neutral or either' of itsextreme positions.

` The change-gear train transmits motion from spindle 4 to shaft 6afterthnenusual manner in which the change l'gearingtransmits motionfrom the spindle tothe leadfscrew as engine-lathes are generallyarranged, `and in the present case the change-gearlv system, so far asits changeability is on'ceinedfmay be ignored,as its changeabilitybecomes of utili-ty only when it becomes necessary to exceed the rangeof feed variations obtainable from the other features of the presentmechanism. Shaft 6 may therefore be looked upon as a shaft turningcontinuously at constant rate in unison with the lathe-arbor. Byappropri ately adjusting bracket 14 idle gear 16 constantly driven bylong pinion l1, may be caused to mesh with any selected one of conegearsl2, the device thus providing for the transmission of selective speedsto shaft 9 from the uniformly-rotating shaft 6. With tumbler 22 in theposition indicated in Fig. 4 the turning of shaft 9 is without eect; butif tumbler 22 be so adjusted as to put gear 23 into mesh with gear 19then shaft 9 transmits motion to the lead-screw, and at suchrate'relative to that of shaft 6 as is determined by the selectedcone-gear. Variable motion may thus be given to the lead-screw from theuniformly-rotating lathe-arbor, thus providing for various pitches ofscrews to be cut by the lathe. If tumbler 22 be so adjusted as to putgear 23 into mesh with gear 20, then motion becomes transmitted to thesplined feed-rod at a rate relative to that of shaft G dependent on theselected cone-gear. Provision is thus made for getting selective speedsto either the lead-screw or the feedrod from the uniformly-rotatinglathe-arbor.

Considered as a device for transmitting the feeding motion in anengine-lathe the described provisions indcate about all of :its usefulcapacities, it being understood, of course, thatif the range ofvariation in speeds obtainable from the cone-gears is insuiiicient thenrecourse may be had to the train of change-gears by the usualtransposition, substitution, &c.; but the transmission of feedmotion ina lathe is but a single example of the applicability of the presentsystem, and it is obvious that shaft 6 may be viewed broadly as auniformly-rotating driver, which by means of the present system ofgearing may be caused to transmit rotation at selective speeds to shaft9 as a driven shaft or beyond that to either of two selective shaftsrepresented by lead-screw 17 and feed-rod 18. Conversely, shaft 9 may beviewed as a unifo1mly1'otating driving-shaft from which the system ofgearing permits rotation at selected rate to be transmitted to shaft 6as a driven shaft, and instead of viewing shaft 9 as the driving shaftit may be viewed as an inter mediate shaft, deriving motion either fromgear 19 or gear 20, selectively, under which circumstances itis manifestthat shaft 6 When viewed as a driven shaft may receive rotation atselected rate from either gear 19 or gear 20.

I claim as my invention- 1. In variable-speed gearing, the combination,substantially as set forth, of a first shaft, a shaft paralleltherewith, a series of dissimilar-sized gears fast on the first shaft, agear fast on the second shaft having a length equal to the length of theseries of gears on the first shaft, a slotted wall-like support disposedconcentric and parallel with said second shaft, a bracket seated uponthe inner surface of said support and longitudinally and angularlyadjustable upon the inner surface of said support, and a gear carried bysaid bracket and constantly engaging said long gear and adapted forengagement with any of said dissimilar-sized gears.

2. In variable-speed gearing, the combination, substantially as setforth, of two parallel shafts, selective gearing connecting said twoshafts and adapted to serve in transmitting motion from one to the otherat selective speeds, a third shaft and a fourth shaft arranged parallelwith each other and With their axes parallel with those of thefirst-mentioned shafts, a gear on the third shaft, a gear on the fourthshaft in the plane of the one on the third shaft, a gear on one of saidfirstmentioned shafts in the plane of those on the third and fourthshafts but free of engagement therewith, a rocking tumbler, and a gearcarried by said tumbler and constantly engaging the last-mentioned gearand adapted to engage the gear on the third shaft or the gear on thefourth shaft.

FREDERICK W". GORDON.

Vitnesses:

W. M. Sronns, CHAS. S. MUNGER.

